More than 50 people were injured in the Aurora shooting. Twenty still remains in hospital.

Holmes legally purchased his guns, gas canisters and thousands of rounds of ammunition, according to prosecutors. The suspect booby-trapped his apartment with explosives, which were deactivated by police after the day after the massacre.

Holmes appeared in court on Monday and is due to be charged next week.

This week, an image went viral, suggesting that guns are easier to buy than French cheese due to restrictions dairy products made with raw milk.